Cutter mechanism



Ham 26, w37., R. K. JEFFREY CUTTER MECHANISM Filed May 1o, 1935 ATT'Y N@M miv @w w. EMWIN w. mf l www@ Patented Jan. 26, 1937 UNITED STATESPATENT OFFICE CUTTER MECHANISM ration of Ohio Application May 10, 1935,Serial No. 20,825

In Great Britain August 27, 1934 12 Claims.

One object of the invention is to provide a cutter bar for akerf-cutting mining machine, which cutter bar is of extremely simple andrugged construction, built up or fabricated from steel plates by aprocess of welding.

Another object of the invention is to provide a new cutter chain andcutter bar which provide a maximum bearing surface therebetween adjacentthe free or head end of said cutter bar Where the cutter chain changesits direction of travel.

Other objects of the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

l- In the accompanying drawing,

Fig. 1 1s a plan View of a mining machine 1ncluding the cutter mechanismcomprising my invention;

Fig. 2 is a lateral elevational sectional View on the line 2 2 of Fig.l;

Fig. 3 is a longitudinal elevational sectional View on the line 3 3 ofFig. 1;

Fig. 4 is a sectional View of a detail taken on the line 4 4 of Fig. l;

Fig. 5 is an enlarged detail plan View showing the head end of thecutter bar and cutter chain with the cutter bar top plate removed andthe cutter chain cut short; and

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Fig. 6 is a sectional view on the line 6 6 ofA Fig. l.

Referring to Fig. l of the drawing, there is seen a mining machine,particularly of the type adapted for cutting kerfs in a coal mine,comprising a body portion it which carries a motor II and has a headsection I2. Adjacent the rear portion of the body |51 there is providedcomplete control mechanisms including a pair of winding drums to whichare attached draft cables i3 for conveying the machine about a mine roomand performing Various kerl-cutting operatlons. Said mining machine mayin general follow the form disclosed in full detail in the applicationof Robert K. Jeffrey and Lewis E.

Mitchell for a Mining machine, Serial No. 716,160, illed March 17, 1934.

Projecting forwardly from the head section I2 of the machine is a posti5 adapted to support a cutter bar I5 in sliding relation. The cutterbar I5 is provided with a circumferential groove or track I within whichis adapted to travel a continuous cutter chain ll formed of alternatebit carrying links I8 and connecting links I9 pivotally connected bypins I8. Appropriate cutter bits 2|) are carried by the bit carryinglinks I8. It is obvious that as the cutter chain progresses around thecutter bar I5 it may be directed to cut a kerf in a mine room in amanner described in complete detail in the aforementioned application.

Attention is particularly directed to Figs. 2, 5 3, and l of the drawingwhich illustrate the important construction of the cutter bar of myinvention. This cutter bar is preferably built up or fabricated fromsteel plates, such as rolled plates, most of which are of simple andstandard 10 form, which are integrally connected as by welding, andpreferably by electric welding, to form a rigid and thus a strong, butlight weight construction. f

The mining machine illustrated in Fig. 1 is of l5 the Shcrtwall typewith the feed rope |3 reeved around the pulley |2' and the retardingrope I3 associated with the pulley II in a well-known manner, to eiTectfeeding movement of the kerfcutter transversely o-f itself. It should beunder- 20 stood, however, that the cutter bar structure may also be usedin longwall mining machines or other types of mining machines.

The cutter bar illustrated in the accompanying drawing comprises a headplate or block 42| .25 which may be a casting or forging and which ispreferably H-shaped in cross-section, as shown in Fig. 2Which is a Viewtaken on the line 2 2 of Fig. 1 looking in the direction Yoi the arrows.Elongated approximately rectangular plates 22 30 and 23 are welded tothe upper and lower parallel faces of the head block 2| and a pair ofside plates 2l' and 28 each equal in length to the plates 22 and 23, arewelded to the head block 2| and to the plates 22 and 23 so as to occupy-35 spaced-apart parallel positions as shown in Figs.

1 and 2.

The welding together of the plates 22, 23, the head block 2|, and theside plates 21 and 28 may be effected in various ways. For instancarthev4.0 edges of the head plate or block 2| may be chamfered and welded at26, 26 to the longitudinally extending side plates 21 and 28 in suchrelation to the head block 2| as to occupy predetermined positions withrespect to the plates 22 and 23 45 when the latter are assembled.

`Each of the cutter bar plates 22 and 23 is provided with ve holes 24,as shown in Fig. l. These holes may be drilled and counter-sunk as shownin Figs. 2 and 3. To effect the welding 50 of the plates 22 and 23 tothe head block 2|, the latter may be connected to one terminal of anelectric welding apparatus, and the welding rod of said apparatus meltedby contacting the same With said head plate 2| at the holes 24 thereby.55

forming head rivets 25, 25 one in each of the holes 24. It will thus beseen that the plates 22 and 23 may be rigidly connected to the headblock 2| so as to be in spaced parallel relation and in predeterminedpositions with respect to the head block 2|, as illustrated in Figs. 1and 3.

It is preferred to connect the side plates 21 and 28 to the cutter barplates 22 and 23 throughout their entire lengths. This may be done bychamfering the edges of the plates 21 and 28 at their outer edges andthen efecting welding of the side plates 21 and 28 at 25', 26' to theplates 22 and 23, as illustrated in Fig. 2. If desired the side plates21, 28 may iirst be welded at 26, 2S to the head plate 2| followed bywelding at 23', 26 of the plates 22 and 23 to the side plates 21 and 28,and finally welding the plates 22 and 23 to the head plate 2| by meansof the Welding rivets 25, 25.

It should be particularly noted that when the head block 2|, side plates21, 28, and cutter bar plates 22 and 23 are assembled by welding inproper relation to each other, the rear inner surfaces of the sideplates 21 and 28 are in position to slide along the vertical side wallsof the post I4. In other words, the side plates 21 and 28 cooperate withthe spaced-apart parallel plates 22, 23 to provide a guide for theadjustment of the cutter bar in length, along the supporting post Ill.The outer surfaces of the side plates 21 and 23 cooperate with thelaterally projecting portions of the plates 22 and 23 to form a U-shapedguideway I6 for the endless cutter chain I1.

By reason of the complete absence of rivet holes in the side plates 22and 23, the side plates may be located by welding closer to the outeredges of the plates 22 and 23 than would be possible if the plates 21and 28 were riveted to the plates 22 and 23. Consequently, wider spacingbetween the side plates 21 and 28 enables the post I4 to be widened andthe plates 21 and 28 to be made of ample thickness while maintainingsuflicient space to form the guideways I6.

The outer end portion of the head block 2| is semi-circular as viewed inplan in Fig. 5. The outer curved section of the head plate or block 2|is provided with upper and lower guide plates 3D and 3| respectively,preferably composed of hardened steel. These upper and lower guideplates 30 and 3| are shown in Figs. l and 5 connected by rivets 32 tothe outer semi-circular portion 2G of the head block 2|. The plates 3Dand 3| may be renewed when worn, by removing the rivets 32, and thenriveting new guides to the semi-circular portion 29 of the head block 2I.

The guide plates 30 and 3| are semi-circular at their outer ends and areprovided with semi-circular guideways I6', I6 which at their rear endsare in alinement with the forward ends of the guideways I6, I6. Thebottoms of the guideways I6', I6 form arcuate surfaces along which thechain links may slide while the chain is traveling around the outer endof the cutter bar. In other words, the bottoms of the guideways I6provide large bearing areas for the cutter chain as it slides around thehead end of the cutter bar I5.

As shown in Fig. 5, the bit holder links I8 are each provided withlaterally projecting flanges or gibs 36 which are adapted to move alongthe guideways I6, I6 at the outer sides of the side plates 21 and 28 andalong the guideways IB' at the outer end portion of the cutter bar.These gibs 36 are provided with arcuate surfaces 31' having a curvedconguration similar to that of the arcuate surfaces 30', 3|' at thebottoms of the guideways I 6. It is thus evident that over a substantialportion of the area of the arcuatesurfaces 33 and 3| there is a slidingcontact between the bit carrying links I8 and the plates 38 and 3|.

The intermediate links I9 which connect the bit holding links I8 areeach provided with arcuate surfaces I9 which are adapted to co-operatewith the arcuate surfaces 33 and 3| on the adjacent inner arcuate webportions of the plates 30 and 3l respectively. As shown in Figs. 3 and 6the bottoms of the guideways I5 are each U-shaped in cross-section andsemi-circular as viewed in plan. Consequently the bottom or inner'central portion of both the connecting links I9 and the bottom centralportions of the side plates of the bit holding links I8 have arcuatesurfaces adapted to make sliding contact with the semi-circular tracks3U and 3|" and 30' and 3|' of the plates 3U and 3|. The sliding contactbetween the curved surfaces I9', 31 and the bottoms of they guideways I6will therefore be extended over a considerable area at the outer end ofthe cutter bar as the cutter chain slides around the same. Thisdistribution of the contact area between the chain and the plates 38, 3|reduces to a minimum the wear on both the cutter bar plates 38 and 3|and on the bottoms of the links of the cutter chain. Inasmuch as thecurved surfaces I9 and 31 at the bottoms of the chain links areelongated in the direction of the travel of the chain, undesirabletilting of the links on axes extending transversely of the cutter bar,will be avoided. In other words, the area of sliding contact between thecutter chain links and the arcuate guiding surfaces at the outer end ofthe cutter bar is so distributed as to maintain a continuous and emcientpath of cutting travel for the cutter bits 2|) during operation of themining machine.

Adjacent the edges of the cutter bar plates 22 and 23 are attached bymeans of removable rivets 34, wear plates 33 which are L-shaped incross-- section, as shown in Fig. 2. The wear plates 33 are adapted tomake an inter-locking iit with the gibs 3G and the outwardly extendingflanges 35 of the bit holding links I8. The Wear plates 33 are locatedbetween the guide shoes 38, 38 and the outer ends of the plates 22, 23.The sides of the bit carrying links t the inner edges of the wear plates33 and the outer flanges 35 so closely that the bottoms of the chainlinks do not contact with the outer surfaces of the side plates 21 and23, but instead the thrust during feed of the chain cutter is taken bythe flanges 35 bearing on the outer surfaces of the wear plates 33. Thatis to say, when the chain cutter is traveling in the direction of thearrow lI8 of Fig. l and the chain cutter is being fed in the directionof the arrow G9, the feeding thrust will be taken by the outer surfacesof the wear plates 33.

It is desirable to stagger the cutter bits 2G in fan-shaped relation asillustrated in Fig. 2 so as to secure the cutting of a wide kerfaffording ample clearance for feeding movement of the cutter bar. Whenthe cutter bits 29 are located in such positions as those shown in fulllines in Fig. 2, there is a tendency during feeding movement in thedirection of the arrow 59 of Fig. l, for tilting movements of the bitholding links to be effected on an axis parallel to the path of travelof the chain cutter, but this tendency is eectively resisted by theinterlocking relation between the gibs 33, the flanges 35, and thesurfaces of the wear plates 33 at the sides the cutter chain comes incontact With.

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While at the sides of the cutter bar the flanges 35 slide along the wearstrips 33 and the bottoms of the chain links do not engage the adjacentsurfaces of the plates 21 and 28, a reverse arrangement is made at theouter semi-circular portion of the cutter bar. In other words, at thehead end of the cutter bar the flanges 35 of the bit carrying links i8are held out of contact with the guide plates 3e and 3|, and to assurethis the bottoms of the flanges 35 are cut away at 35 along arcuatelines, as shown in Fig. 5.

Near the rear end of the cutter bar the plates 22 and 23 are providedwith guide shoes 38, 38, as shown in Figs. l and 4, to provide taperedguideways leading to the side grooves I5, I6 of the cutter bar. Thisprovision is made to assure proper entry of the gibs 35 oi the bitcarrying links 68 into the side grooves i8 so that the gibs 36 andflanges 35 will fit over the wear strips 33,

as shown in Fig. 2. The gibs 36 are beveled at both ends as indicated at36 in Fig. 5, to cooperate with the guide shoes 33, 38. Such beveling at35 also facilitates entry of the gibs 33 along the beveled ends 33 intothe guideways I6 back to the wear strips 33.

It should also be noted that when the ropes i3, I3 are arranged toeffect sumping of the kerf-cutter into a mine vein lengthwise of thecutter bar preparatory to shortwall operations, the rather close fitbetween the sides of the bit carrying links and the inner walls of theguideways i6", IS will prevent tilting of those cutter bits which areinclined to the greatest angle relative to the plane of the cutter bar.The sides of thebit carrying links willr bear against the innerspaced-apart parallel walls 5B, 5i) which are semivcircular inconfiguration and parallel to the planes which extend through the upperand lower surfaces of the cutter bar. The gibs 36 bear against thespaced-apart parallel walls 5l, 5I which are also semi-circular andconcentric with the curved walls 50. The inner edges of the side platesof the bit carrying links bear against the walls 52 which are alsosemi-circular and concentric with the curved walls 50.

It will thus be seen that the side plates of the bit carrying links areextended laterally and outwardly at their lower inner ends to form thegibs 36. The side plates of the bit carrying links together with thegibs 36 ride in arcuate spacedapart grooves which are in verticalalinement as viewedin Fig. 3. The gibs 35 are also movable alongparallel spaced-apart grooves which `are of sufiicient dimensions toafford freedom of movement of the elongated gibs 36 while thechain'passes around the curved outer end of the cutter bar.

By comparing Figs. 2 and 3, it will be seen that the chain makes aninterlocking connection with the cutter bar both at the sides or edgesof the chain and at the outer curved end thereof, and tilting of thosecutter bits which are located at the maximum angle, as shown in fulllines in Figs. 2 and 3, is effectively prevented not only at the sidesor edges of the Vcutter bar but also at the outer curved end thereof.The guides 38 lead the chain into interlocking connection with theL-shaped wear strips 33, as shown in Figs. 1 and 2, and from the outerends of the wear strips 33 the chain is led into a guideway l5 intointerlocking relation with the head sections 3i), 3l. After movingthrough a semi-circle the chain again goes into interlocking relationwith the leading side of the cutter bar, as shown in Fig. 2. Byobserving the relationship between the grooves Aof standard shape.

.renewable.

of the vguideways I6 it will be seen that the cylindrical grooves at 30.3| are at right angles to the spaced-apart parallel grooves 5I, 5! andthe latter are in parallel relation to the semi-ring surfaces 5 6, 50.Furthermore, although the laterally extending iianges 35 of the bitholding links bear against the outer surfaces of the Wear strips 33along the leading and trailing edges of the cutter bar they are held outof contact with the cutter bar, as shown at 35 in Fig. 3, when thecutter chain is traveling around the curved end of the cutter bar.

For the purpose of adjusting the slack in the cutter chain l1 ascrew-threaded shaft 39 is screw-threaded through an opening in theblock 42 which is riveted between the plates 22 and 23, as shown inFigs. 1 and 3. If desired the block 42 may be welded to the plates 22and 23 in a manner similar to the welding of the head block 2| to theplates 22 and 23.

The shaft 39 is provided with a head 4D tting a cylindrical opening inthe outer end of the post I4. Between the threaded portion 4l of theshaft 39 and the head 40 thereof is located a wheel 44 having radiallyspaced-apart recesses 45. When the wheel 44 is turned in one directionor the other, the length of the cutter bar may be adjusted, after whicha U-shaped locking device 46 having a central pin may be inserted in theopening 41 of the top plate 22. The pin of the locking device 46 willfit any one of the radial rholes in the Wheel 44 so as to lock the shaft39 against rotation after it has once been actuated to effect adjustmentof the slack in the cutter chain. When the locking device 45 is removed,'1

a tool may be inserted in one of the radial openings to eiect turning ofthe screw 4l. Instead of depending upon frictional contact between thelocking` device 46 and the top plate 22, a set screw 46 may be providedto hold the locking device 46 securely connected to the wheel 44, asshown in Fig. 3.

In view of the foregoing disclosure of an embodiment of my invention, itis evident that a mining machine cutter bar may be constructed so as tobe Very strong and still relatively light in weight. The cost ofconstruction is materially reduced because the cutter bar may be readilybuilt up from rolled steel plates most of which are the cutter bar isreduced to a minimum while its strength is increased and the cost ofconstruction reduced.

It should also be noted that the surfaces which receive the most wearare located on pates 30, 3l,

and 33, all of which Yare removable and therefore While the relationbetween the cutter chain and the wear strips 33 is for efficieroperation during feeding movement in the direction of the arrow @.3 ofFigi. 1, the relation between the chainand the outer semi-circularguideways is for efficient entry of the cutter bits into their cuttingpaths of travel while changing direction or moving arcuately. That is tosay, the particular arrangement at the outer end of the cutter bar isespecially for the purpose of not only reducing the wear to a minimum,but also to secure efloient initial operation of each cutter -bit as itenters its cutting path of travel and moves arcuately to the leadingside or edge of the cutter bar.

Obviously those `skilled in the art may make various changes in thedetails and arrangement of parts without departing from the spirit andConsequently the weight of scope of the invention as dened by the claimshereto appended, and I therefore wish not to be restricted to theprecise construction herein disclosed.

Having thus described and shown an embodiment of my invention, what Idesire to secure by Letters Patent of the United States is:

1. In a mining machine, the combination with a cutter bar, of a cutterchain, said cutter bar having chain receiving guideways adjacent eachside thereof and a head portion forming a curved guideway with anarcuate bearing surface adjacent the inner wall thereof, said cutterchain comprising bit carrying links and connecting links, the bitcarrying links having bearing flanges which contact with the outsideedges of the cutter bar adjacent the longitudinal sides thereof, andhaving outwardly extending gibs having arcuate bottom surfaces whichcontact with said arcuate bearing surface of the head portion of saidcutter bar, and said connecting links also having arcuate bottomsurfaces which contact with said arcuate bearing surface of the headportion of said cutter bar.

2. In a mining machine, the combination with a cutter bar, of a cutterchain, said cutter bar having chain receiving guideways adjacent eachside thereof and a head portion forming a curved guideway with anarcuate bearing surface adjacent the inner wall thereof, said cutterchain comprising connected bit carrying links and connecting links, thebit carrying links having bearing flanges which contact with the outsideedges of the cutter bar adjacent the longitudinal sides thereof, andhaving retaining gibs with arcuate bottom surfaces which contact withsaid arcuate bearing surface of the head portion of said cutter bar.

3. In a mining machine, the combination with a cutter bar, of a cutterchain, said cutter bar having a curved end with curved bearing surfaces,one of which is on a central arcuate boss of said curved end and a pairof which are on each side of said boss, said cutter chain having bitcarrying links with arcuate bottom surfaces which ride on said pair ofsurfaces and connecting links with arcuate bottom surfaces which ride onsaid one surface on the central arcuate boss.

4. A cutter bar for a mining machine comprising spaced top and bottomplates, longitudinal side plates positioned between said top and bottomplates, a head plate positioned between said top and bottom plates, andbetween said side plates and located at one end of said cutter bar, allof said plates being welded together to provide a rigid cutter bar.

5. In a mining machine, the combination with a cutter bar, of a cutterchain, said cutter bar forming a longitudinal guideway adjacent its sideedges for said cutter chain, gibs on said cutter chain adapted to travelin said guideway, retaining means adjacent said guideway co-operatingwith said gibs to hold said cutter chain on said cutter bar, and aremovable guide shoe adjacent the point of entry of said chain gibs intosaid guideway for guiding said gibs thereinto, said shoe having atapering guideway leading to said cutter bar guideway.

6. In a mining machine, the combination with 'L cutter bar having acurved outer end, of semicylindrical grooves spaced apart within theouter semi-circular portion of said cutter bar, a cutter chaincomprising cutter carrying links and connecting links, said cuttercarrying links having spaced-apart side portions adapted to ride alongsaid semi-cylindrical grooves while said connecting links travel alongthe space between said grooves, and means for guiding the cutter chainalong the sides of the cutter bar.

7. In a mining machine, the combination with a support, of a cutter barcomprising spacedapart parallel plates welded to spaced-apart elongatedstrips to form a socket fitting over said support, a head block weldedbetween the outer ends of said plates and having a semi-circular portionprojecting therefrom, a pair of guide plates removably secured to thesemi-circular portion of said head block, and means affording guidewaysfor cutter chains along the sides and cuter end of said cutter bar.

8. In a mining machine, the combination with an elongated support, of acutter bar comprising spaced-apart parallel plates welded to spacedapartparallel strips to form a socket fitting said support, a cutter chain,interlocking guideway connections between said cutter chain and saidcutter bar, a stationary nut secured to said plates to occupy a positionbetween the same, means connected to said support and screw-threadedthrough said nut to adjust the slack of the cutter chain, and meansassociated with an opening in one of said plates for holding the slackadjusting mechanism in adjusted position.

9. In a mining machine, the combination with a cutter bar having a headwith spaced arcuate bearing surfaces of different radii, of a cutterchain having interconnected bit carrying links and connecting links,both of said links having arcuate bearing surfaces which contact thehead bearing surfaces as said links move around said head.

10. In a mining machine, the combination with a cutter bar having a headwith spaced arcuate bearing surfaces of different radii, of a cutterchain comprising interconnected bit carrying links and connecting links,arcuate bearing surfaces formed on each of said types of links, one typeof link contacting a bearing surface of one radius and the other type oflink contacting a bearing surface of the other radius as they movearound said head.

1l. In a mining machine, the combination with a support, of a cutter barcomprising spacedapart parallel plates rigidly attached to spacedapartelongated strips to form a socket tting over said support, a head blockrigidly attached between the outer ends of said plates and having anarcuate portion projecting therefrom, and a pair of guide platesremovably secured to said arcuate portion and forming an arcuateguideway having bearing surfaces of different radii.

l2. A cutter bar comprising an elongated body portion and a head portionat one end, said head portion including a pair of plates providingspaced apart arcuate bearing surfaces with an arcuate boss between them,said boss having an arcuate bearing surface.

ROBERT K. JEFFREY.

